Effect of Intracameral Injection of Bisulfite-Containing Phenylephrine on Rabbit Corneal Endothelium

Purpose: The aim of this study was to investigate the effect of intracameral injection of bisulfite-containing phenylephrine on rabbit corneal endothelium cells in rabbits. Methods: Fifteen eyes of 15 New Zealand white rabbits were divided into 3 groups. Five eyes from each group were injected with 0.5% (0.5 mL, 0.05% bisulfite, group 1), 1.0% bisulfite-containing phenylephrine (0.5 mL, 0.1% bisulfite, group 2), or an equal volume of balanced salt solution as a control (group 3). Specular microscopy, corneal pachymetry, and a slit-lamp examination were used to evaluate corneal endothelial cell loss and other complications before injection, and at 1 hour and 1 week after injection. For morphological studies, corneal buttons were excised at 1 week and stained with alizarin red and trypan blue. Optical microscopy was used to examine 1 cornea from each of the 3 groups. Results: Within each group, there were no changes in specular microscopy and corneal pachymetry findings over the 1-week duration of the study. Although all groups showed the presence of several giant cells in the endothelium, the hexagonal shape of the corneal endothelium was morphologically preserved, and no abnormal endothelial cells were observed. Conclusions: Intracameral injection of bisulfite-containing phenylephrine (up to 1.0%) does not affect endothelial cell viability or morphology of the rabbit cornea.